public class Example4_9 {
    public static void main (String args[]) {
        SIM simOne=new SIM(13889776509L);
        MobileTelephone mobile=new MobileTelephone();
        mobile.setSim(simOne);
        System.out.println("手机号码："+mobile.lookNumber());
        SIM simTwo=new SIM(15967563567L);
        mobile.setSim(simTwo);
        System.out.println("手机号码："+mobile.lookNumber());
    }
}
